Autism Spectrum Disorders (ASD) are neurodevelopmental disorders that affect people across their lifespan. Among those without an intelectual disability, the disorder may not become apparent until adulthood, when it usually presents with comorbidities.

As ASD symptoms are poorly recognized and assessed in adulthood, and the diagnosis is made easier by the application of appropriate evaluation scales, we intend to identify and describe all tools available for screening or diagnosing ASD in adults without intellectual disabilities, and report their psychometric properties.

Pubmed, PsycINFO and Embase database search up until September/2014, using 'high-functioning autism” or 'Asperger” and 'adult”, combined with 'questionnaire”, 'assessment”, 'instrument” or 'scale” as search terms.

We identified 14 instruments, including observational scales, interviews and self-report questionnaires, among which seven are specifically designed for adults. Time to administer and training required vary widely. Psychometric properties are generally good, although validation is scarce. Six instruments are designed for screening purposes: ASQ and its shorter version (ASQ-10), RAADS-14, ASDASQ, KADI and ASSERT. The remainder are intended to be diagnostic: ADI-R (with adaptations – deleted items), ADOS-G Module 4, AMSE, GADS, ASDI, RAADS, AAA and SRS-A.

Besides the time-consuming gold-standard instruments (ADI-R and ADOS-G), there are many instruments available for assessing ASD in adults. Nevertheless, lack of enough validation and comparison between these scales prevents making safe recommendations regarding their use.